• Journal of Korean Society of Transportation
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• v.18 no.2
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• pp.63-71
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• 2000

One Problem of the choice Property in logit model is interpreted as the Problem of common links and common nodes in choice set. Common node Problem Plays important role in deciding the efficiency of network loading and common link problem is connected with choice Problem, both of which are to be solved to improve the logit choice model. Although much need has been pointed out for research on the topic, however, no Paper as yet considers these two factors at the same time. In the Paper we develop a new logit formulation, which is able to ease the logit Problem, widely known as the Problem of IIA(Independence of Irrelevant Alternatives). An example network is used to assess the Proposed model and compare it with other conventional models. From the results, we find out that the model is superior to others.

• Journal of the Korean Chemical Society
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• v.46 no.4
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• pp.353-363
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• 2002

In this study, characteristics of the problem solving process of the balancing redox equations was ana-lyzed by mental capacity and problem solving methods, and the pertinent teaching and learning guidance for oxidation-reduction unit was suggested. Participants were 79 senior high school students and 57 science high school students. Tests were conducted to measure the mental capacity, the understanding of the oxidation-reduction concepts and the com-pletion of the balancing redox equations. The framework was made to find the patterns of failure and success. As the analysis of the influence on the performance of mental capacity,understanding of the oxidation-reduction concepts, and problem solving methods, students who had lower understanding of oxidation-reduction concepts selected the trial and error method, and their performance were influenced by mental capacity. The students that had higher understanding of the oxidation-reduction concepts had good performance by using oxidation number method regardless of their mental capacity. As the results of analysis for the patterns, the success patterns of solving the problems, those of mostly the sci-ence high school students, were the cases of using oxidation number method well and lessening problem solving steps. The patterns of failure in solving problems by using trial and error method showed that students had mistakes in cal-culating, errors in making unknown equations, no consideration for all variables, or stopped solving the complicated problems. The patterns of failure in solving problems by using oxidation number method showed that many students had wrong oxidation number or no consideration for mass and charge balance.

• Journal of Korea Entertainment Industry Association
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• v.13 no.5
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• pp.25-36
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• 2019

The purpose of this study was to investigate the effect of fast food intake, choice, and satisfaction on age among 311 people living in the metropolitan area. The frequency of fast food intake was high in the 20s and 30s, and those in the 40s and over 50s were low, showing a significant difference according to age. Costs for fast food purchases mainly ranged from 5,000 won to 7,000 won. Major sources of information on choosing fast food were mainly from friends and the internet in 20s, and mass media from over 30s. Thirty-nine percent of subjects responded that their dietary habits changed after fast food intake, and the most changes was to like spicy food, followed by eating-out times increased. The factors affecting the choice of fast food were mainly easy to eat, followed by time was not influenced and taste, and taste showed significant difference according to age. Among the subjects who were worried about fast food, 30s showed mainly increase in body weight and over 50s had health problem, and a significant difference was observed according to age. For the improvements in fast food intake, subjects answered in nutrition, hygiene and price in order. Fast food brands, services, menus were the most satisfied in 30s, and 40s were the most unsatisfied, and there was a significant difference. In conclusion, the frequency of fast food intake was higher in young people, and the choice of fast food and satisfaction appeared to be significantly influenced by age. Therefore, data are required to recognize and practice a balanced diet by activating studies on the fast food intake of middle-aged and elderly people and understanding consumer changes.

• Korean Journal of Poultry Science
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• v.8 no.1
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• pp.37-45
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• 1981

급격히 증가하는 세계의 인구수는 가축의 사료자원을 질이 좋은 인간 식량으로 효율적으로 전환할 필요성을 절실케 하고 있다. 산란계는 유전적인 선택에 의해 최소량의 사료로써 높은 산란율을 유지할 수 있도록 개선되어 왔다. 배합사료의 생산에 사용될 수 있는 단미사료의 종류와 품질은 어느 특정한 영양소의 요구량에 의하여 좌우된다. 산란계의 영양요구량은 오랜동안 연구되어 왔으며, 미국의 국립연구위원회 (NRC)는 영양소 요구량을 정기적으로 검토, 요약하고 있다. 새로운 정보들은 출판되어 왔으며 본인은 여기서 제7차로 개정된 NRC 사양표준(1977)에 발표된 요구량에 관련해서 몇 가지 분야를 검토하고자 한다. (중략)

• IE interfaces
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• v.9 no.2
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• pp.173-189
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• 1996

부품번호를 할당하고 관리하는 규칙은 모든 제조업체의 운용에 앞서 행해져야 하는 중요한 사항이다. 특히 완성차 제조업체의 경우 2-3만개의 부품이 사용되며, 선택사양의 다양화, 빈번한 설계변경에서의 신속한 대응, 부품확산 방지를 위해서는 효율적인 부품/모듈번호 체계가 필요하다. 본 연구는 H자동차 회사의 기존 부품번호 체계가 가지고 있는 문제점을 해결하기 위해 기존의 코드체계를 검토하여 개선방향을 정립하기 위한 것이다. 이를 위해 1) 제조업의 부품번호 체계와 관련된 이론의 수집/정리 2) 외국 완성차 업계의 번호체계 현황 조사/분석, 3) 완성차 소요부품과 관련된 코드체계의 의미를 명확화, 4) 부품번호의 균형 할당을 위한 작업이 수행되었다.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.581-583
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• 2003

일반적으로, 전력시장은 가격기능을 통하여 공급과 수요의 균형을 이룬다. 경쟁적 전력시장은 가격신호를 통하여 공급측에는 투자 유인을 북돋우고 수요측에는 수요 감소 등의 반응을 유도한다. 이와 같은 전력시장의 특성상 본질적으로 가격 변동성과 신뢰도 유지 및 확보 문제가 수반된다. 본 연구에서는 에너지 단독시장에서의 가격신호를 보완해주는 효과를 지닌 용량의무 mechanism을 선택한 PJM 시장을 중심으로 분석함으로서 해외 전력시장에서의 적정 설비공급 메커니즘을 분석하고자 한다. 따라서, 본 연구의 결과는 향후 우리의 전력시장 설계 및 운영에 일조하리라 믿는다.

• Korean Journal of Biological Psychiatry
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• v.26 no.2
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• pp.33-38
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• 2019

Psychiatric disorder as dysfunctional behavioural syndrome is a paradoxical phenomenon that is difficult to explain evolutionarily because moderate prevalence rate, high heritability and relatively low fitness are shown. Several evolutionary genetic models have been proposed to address this paradox. In this paper, I explain each model by dividing it into selective neutrality, mutation-selection balance, and balancing selection hypothesis, and discuss the advantages and disadvantages of them. In addition, the feasibility of niche specialization and frequency dependent selection as the plausible explanation about the central paradox is briefly discussed.

• Information and Communications Magazine
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• v.32 no.3
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• pp.105-107
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• 2015

2014년 7월 미래부에서 국가재난안전통신망에 대한 기술방식을 최종 선정한 이후로, 국가재난안전통신망에 대한 관심이 높아지고 있다. 본고에서는 먼저 본 과제의 필요성 및 주요 성과물을 다루고 현재의 R&D 시장 동향을 통해 어떤 전망을 내다볼 수 있는지 구체적으로 다룬다. 궁극적으로 재난통신 시스템 및 단말 개발은 미래부에서 요구하는 재난망의 필수/선택 기준을 만족시키는 원천 기술 확보 및 이에 대한 표준화 그리고 상용 수준의 시스템 및 단말이라는 요소들을 모두 균형적으로 고려하여 이루어져야 한다.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10b
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• pp.96-98
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• 2000

본 논문에서는 상거래 환경에서 구매자와 비구매자들에 대한 데이터를 학습한 후, 잠재고객들 중에서 구매 확률이 높은 사람을 예측하는 문제에 효율적으로 접근하기 위해 능동적인 데이터 선택 기법을 이용한다. 실험 데이터는 ColL Challenge 2000에서 얻은 데이터로서, 구매자들의 정보보다 비구매자들의 정보가 더 많기 때문에 상당히 균형이 맞지 않는다. 따라서 모든 데이터를 한꺼번에 학습하는 경우에 성능이 좋지 않다. 본 논문에서는 이러한 불균형 분포를 갖는 실제적인 문제에 있어서 성능이 좋지 않다. 본 논문에서는 이러한 불균형 분포를 갖는 실제적인 문제에 있어서 RBF 기반의 신경망을 가지고 능동 학습을 함으로써 기존의 뱃치학습 보다 예측의 정확도를 향상시킬 수 있음을 보인다.

• Korean Journal of Childcare and Education
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• v.11 no.1
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• pp.101-128
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• 2015

The purpose of this study was to investigate early childhood pre service teachers' perception on the meanings of free play and the roles of teachers in charge of free play hours. For this purpose, this study analyzed reflective journals, metaphorizing, image drawings, and interview records made by 69 junior students majoring in Early Childhood Education and participating in the practice of child care. According to the results, the meanings of free play perceived by the early childhood pre service teachers were summarized into 'an exciting festival,' 'a fenced playground,' and 'a journey for learning.' In addition, their perceptions on the roles of teachers in charge of free play hours were summarized into 'accompanying teacher,' 'leading teacher,' 'correcting teacher,' and 'encouraging teacher.' These results suggest the need of systematic education through pre service curriculums that help early childhood pre service teachers form a balanced view and perception on the meaning of free play and the teachers' role performance.